The Comparison of the Gluteus Maximus Activity during Various Prone Hip Extension in Subject with Chronic Low Back Pain

PURPOSE: Prone hip extension (PHE) has been used for assessment of lumbo-pelvic movement and strengthening exercise for weakness of the hip joint muscles in patients with chronic low back pain (CLBP). On the other hand, few studies have examined which are the best PHE exercises to activate the gluteus maximus (GM) selectively in physical therapy practice. To aim of this study compared the muscle activity of the GM, rectus femoris (RF), biceps femoris (BF), tibialis anterior (TA) during these four different prone hip extensions, PHE, PHE with quadriceps activation (PHEQA), PHE with ankle dorsiflexion (PHEAD), and PHE with ankle plantarflexion (PHEAP), in subjects with CLBP. METHODS: Nineteen subjects with low back pain participated in this study. Subject performed four PHE exercises and surface electromyography (EMG) was used to evaluate the muscle activity. Data were analyzed by one-way repeated-measures analysis of variance (${\alpha}=.05/3=.017$) and a Bonferroni adjustment was performed if a significant difference was found. RESULTS: The muscle activities recorded by EMG showed significant among the four exercises. The muscle activity of the GM increased significantly during PHEQA than during PHEAP (P=.012). CONCLUSION: PHEQA is the most effective exercise for eliciting greater GM muscle activation among the four PHE exercises in subjects with CLBP.